function RepeatedImgLayer(a, b, c, d) {
    this.initialize();
    d = a.width + d;
    b += d;
    this.graphics.bf(a).r(0, 0, b, a.height);
    this.setBounds(0, 0, b, a.height);

    // 图片属性初始化或者只是采用默认值后，通过修改属性创建动画
    this.animation = createjs.Tween.get(this, {loop:true}).to({x:-d}, d / c * 1000);
    this.do_cache();
}
RepeatedImgLayer.prototype = new createjs.Shape;
RepeatedImgLayer.prototype.setPaused = function (a) {
    this.animation.setPaused(a);
};